Power transmission device



April 12, 1938. r H. FCTTINGER POWER TRANSMISSION DEVICE Filed Oct. 1, 1956 Inventor Hermann Fttinger; b 5.

Hi Attorneg.

Patented Apr. 12, 19 38 UNITED STATES POWER- TRANSMISSION DEVICE Hermann Fiittinger, Berlin-Charlottenburg,

Germany Application October 1,

1936, Serial No. 103,600

In Germany October 11, 1935 2 Claims.

My invention relates to power transmission devices, and more particularly to a device comprising a hydraulic power transmitting gear having its elements connected to the elements of a mechanical gear train. I

An object of my invention is to provide an improved gear train which may be readily connected to the elements of a hydraulic power transmission device.

Another object of my invention is to provide an improved mechanical and hydraulic transmission wherein the hydraulic transmission is developed as a single stage device.

For a better understanding of my invention, together with other and further objects thereof, reference is had to the following description, taken in connection with the accompanying drawing, and its scope will be pointed out in the appended claims.

Referring to the drawing, Fig. 1 illustrates a built in accordance with my invention, and Figs. 2 and 3 are vertical cross-sectional views of modiflcations thereof.

Referring to Fig. 1 in detail, I have illustrated a power transmission device comprsing a gear train A and a hydraulic device B. The gear train A is an improved form of an epicyclic train whereby power from a drive member is divided and transmitted to a driven member through two channels, one channel being a direct mechanical connection and the other channel being through the hydraulic device B. The drive member, shaft It, of this transmission is mounted in a suitable 0 bearing ii and is connected to a sun gear I2 of the gear train A. Engaging the gear I2 are several pinions I3, each of which comprises two planet gears I4 and I 5, of different diameters, rigidly connected to each other on a common shaft IS. The gears I5 of the pinions I3 engage a second sun gear Il mounted on a shaft I8 which, in the present case, is the driven membar. The driven shaft I8 is in axial alinement with the drive shaft I0 and the gears I2 and I! are parallel to each other, being connected only through the pinions I3. This gear train, comprising gears l2 and I? connected by the pinions I3, of which the gears I l engage the gear l2 and gears I5 engage the gear ll, comprises an improved epicyclic gear train in which the gears l5 and I? take the place of the usual internal gear provided in the standard and well-known epicyclic gear train.

The above-described improved gear train constitutes a simplified gearing for connection to or vertical cross-section of a power transmission operation with the hydraulic device B. The hydraulic device B is a power transmitting device 'capable of being used as a slip coupling or as a speed reducing device. It comprises a casi g in which a fluid is set into motion by a wheel 5 having properly shaped vanes thereon. The energy imparted to this fluid is absorbed by a second wheel also having vanes thereon and is thereby caused to rotate. In order to facilitate the flow of fluid between the two wheels, which may be termed the pump and turbine wheels respectively, a third wheel or set of vanes may be used. This third set of vanes is usually stationary and is for convenience attached. to the casing of the device. Further details of this type of hydraulic coupling and speed reducing device are set forth in my U. S. Patents No; 1,199,359 and 1,199,360, issued September 26, 1916.

In the device illustrated in Fig. 1 the driven shaft l8 has mounted upon it the turbine wheel 20 I9 of the hydraulic device 13 and the pinion shafts it are connected to the pump wheel 20 of the same device through a disc or spider 2| mounted upon a hollow shaft 22 which is concentric with the driven shaft I8 and is mounted in bearings 23 and 24. The turbine and pump wheels l9 and 20 are provided with vanes for circulating the fluid provided in the casing 25 in the direction indicated by the arrows. The casing 25 is stationary. It supports the bearings 24 and 26, and further supports a group of directing vanes 21 which receive the circulating fluid from the turbine wheel I 9 and redirect it to the pump wheel 20. With this are rangement it will be evident that power is transmitted to the shaft l8 from the shaft I0 through the pinions I3. If these pinions are stationary upon their own shafts It a direct transmission of power takes place between the shafts I 0 and I8, their respective speeds of rotation being equal, but a rotation of these pinions about their axes and the resultant relative movement between the hollow shaft 22 and the driven shaft I8 changes this direct transmission. by creating a speed difference between the two shafts in proportion to the movement of the pinions about the axis of shaft I8. The speed ratio between the two shafts I0 and I8 is of course controlled by the hydraulic transmission device and is proportional to the load transmitted from the drive shaft to the driven shaft. In the present arrangement of the gear transmission the connection between the elements of. the gear train and the hydraulic coupling are simplified and thereby only a single stage hydraulic coupling is necessary.

In Fig. 2 I have illustrated a modification of my invention wherein the sun gear i1 is connected to the pump wheel 29 of the hydraulic device instead 'of being connected to the turbine wheel l9 as 'shown in Fig. 1. The hollow shaft 22, on the other hand, driven by the pinions i3, is connected to the turbine wheel 30 of the device. In this modification the turbine wheel 33 is mounted upon the casing 3| of the device which is rotatably mounted in bearing 32 and transmits power through a pair of gears 33 and 34 ,to a shaft 35. The gear 33 is mounted on a sleeve 36 attached to the casing 3| and comprises the driven member of this transmission. The directing vanes for directing the fluid between the pump wheel 29 and the turbine wheel 30 are mounted upon a wheel 31 which is in turn mounted upon a shaft 38. The shaft 38 is itself mounted rigidly and projects through the sleeve 36 and the center of gear 33 into the casing 3|. In this modification the shaft 38 pro-- vides a convenient means for supporting the stationary wheel 31 and the gears 33 and 34 are therefore necessary to transmit power to an output shaft 35. e

' In Fig. 3 I have illustrated another modification in which the position of the hydraulic device B and the gear train A is reversed, so that the hydraulic gear is now-on the driven side of the transmission. The drive shaft I ii in this modification projects through the hydraulic de-' vice B and is connected to the gear l2 of the gear transmission as in the previous modifications. The driven shaft la in this modification is connected to the spider 2| carrying the pinions l3. The pinion shafts IS in this case project through the pinions and engage a spider 40 which is connected to a hollow shaft 4! concentric with the drive shaft i0 and the hollow shaft 22 and carrice the turbine wheel 42 of the hydraulic device B.. The gear H in this modification is connected to the hollow shaft 22 which carries the pump wheel 43 corresponding to the wheel 20 in Fig. 1. The directing vanes 44 are connected to the stationary casing 45.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. In a power transmission device, the combination of a hydraulic coupling including a pump wheel, a turbine wheel and a set of stationary vanes, and a gear train comprising a pair of sun gears, a drive shaft connected to one of said sun gears, a plurality of pinions each comprising two planet gears engaging respectively said sun gears, a driven shaft attached to said second sun gear and arranged to be driven by said turbine wheel, and means for connecting said pinions to said pump wheel whereby the movement of said pinions about the axis of said sun gears is transmitted to said pump wheel.

2. In a power transmission device, the combination of a hydraulic coupling including a casing, a fluid therein, a pump wheel, a turbine wheel and a set of stationary directing vanes arranged between said turbine and pump wheels, a gear train comprising a pair of sun gears arranged abouta common axis and parallel to each other; a plurality of pinions each comprising planet gears connected to each other and engaging said sun gears respectively, a drive shaft attached to one of said sun gears, a driven shaft attached to said second sun gear, and a third shaft attached to said pinions, and means whereby relative rotation between said driven shaft and said third shaft is regulated by said hydraulic device comprising a connection between said pump wheel and said third shaft and a connection between said turbine wheel and said driven shaft.

HERMANN FO'I'I'INGER. 

